1. Field of the Invention
The present invention relates to an image generating apparatus, and more particularly, it relates to an image generating apparatus comprising a print head.
2. Description of the Background Art
Image generating apparatuses comprising print heads are known in general, as disclosed in Japanese Utility Model Laying-Open Nos. 6-32044 (1994) and 5-51659 (1993) and Japanese Patent Laying-Open Nos. 2003-260809, 2002-103737, 11-115276 (1999) and 60-15173 (1985), for example.
The aforementioned Japanese Utility Model Laying-Open No. 6-32044 discloses an image generating apparatus mounted with a thermal transfer ribbon including an ink sheet end mark portion provided on the terminal of an ink sheet for indicating the termination of the ink sheet and a cleaning portion provided on a position deviating from the forward end of the ink sheet end mark portion toward the terminal of the ink sheet by a constant distance for cleaning a print head. When a sensor provided on the body of this image generating apparatus senses the ink sheet end mark portion in a printing operation, the image generating apparatus completes the printing up to the remaining region of the ink sheet. Thereafter the image generating apparatus removes dirt (dust) adhering to a heating element portion of the print head by pressing the print head against the cleaning portion.
The aforementioned Japanese Utility Model Laying-Open No. 5-51659 discloses an image generating apparatus having a cleaning pad provided on an end of a platen roller for removing dirt (dust) adhering to a print head by moving the print head up to the end of the platen roller along the axial direction of the platen roller while pressing the print head against the cleaning pad upon power supply to the image generating apparatus or in synchronization with an exchange of a ribbon cartridge. The cleaning pad is infiltrated with a solvent, which is replenished by the user when the cleaning pad is dried.
The aforementioned Japanese Patent Laying-Open No. 2003-260809 discloses an image generating apparatus having a photocatalytic layer of titanium oxide provided on the surface of a print head as well as an ultraviolet fluorescent lamp and a reflecting mirror provided in the body of the apparatus. This image generating apparatus removes dirt (dust) adhering to the print head through photodecomposition by applying ultraviolet light from the ultraviolet fluorescent lamp to the print head through the reflecting mirror every time the apparatus completes printing on a paper.
The aforementioned Japanese Patent Laying-Open No. 2002-103737 discloses an image generating apparatus comprising a suction member, having suction holes on a surface coming into contact with a printing/recording paper, provided on an upstream side beyond a print head along a paper feed direction for removing dust from the surface of the printing/recording paper in contact with the suction member by sucking air through the suction holes.
The aforementioned Japanese Patent Laying-Open No. 11-115276 discloses an image generating apparatus comprising an air bag and a nozzle provided in the body thereof, while the air bag is formed by an elastic member having a prescribed thickness to be deformed when receiving external force and self-reset to the original shape when released from the external force. When a cover of the body of the apparatus is closed in printing, a pressing portion provided on the cover presses and deforms the air bag, thereby blowing air from the air bag to a space between a platen roller and a print head for removing dust adhering to the print head or the platen roller.
The aforementioned Japanese Patent Laying-Open No. 60-15173 discloses an image generating apparatus applying a heating temperature higher than that in a printing operation to a print head in an idle period thereby melting dirt such as resin adhering to the print head.
In the conventional image generating apparatus proposed in the aforementioned Japanese Utility Model Laying-Open No. 6-32044, however, the thermal transfer ribbon must be newly provided with the dedicated cleaning portion for cleaning the print head, disadvantageously leading to a complicated structure of the thermal transfer ribbon.
In the conventional image generating apparatus proposed in the aforementioned Japanese Utility Model Laying-Open No. 5-51659, the platen roller must be newly provided with the dedicated cleaning pad for cleaning the print head on the end thereof, disadvantageously leading to a complicated structure of the platen roller.
The conventional image generating apparatus proposed in the aforementioned Japanese Patent Laying-Open No. 2003-260809 must be newly provided with a cleaning-only optical system including the ultraviolet fluorescent lamp and the reflecting mirror for applying the from the ultraviolet fluorescent lamp to the print head in order to clean the print head through a photocatalytic effect. Therefore, the structure of the image generating apparatus is disadvantageously complicated.
The conventional image generating apparatus proposed in the aforementioned Japanese Patent Laying-Open No. 2002-103737 must be newly provided with the air suction mechanism for cleaning on the body thereof. Therefore, the structure of the image generating apparatus is disadvantageously complicated.
The conventional image generating apparatus proposed in the aforementioned Japanese Patent Laying-Open No. 11-115276 must be newly provided with the air bag and the nozzle for removing dust as well as the mechanism for deforming the air bag on the body thereof. Therefore, the structure of the image generating apparatus is disadvantageously complicated.
The conventional image generating apparatus proposed in the aforementioned Japanese Patent Laying-Open No. 60-15173, melting and removing the dirt such as resin, cannot remove thermally infusible foreign matter. Thus, this image generating apparatus is disadvantageously insufficient in cleaning function for the print head.